package com.heze.utils;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;

/**
 * @author 何泽
 * @version 1.0
 */

//sqlSessionFactory --> sqlSession
public class MybatisUtils {

    private static SqlSessionFactory sqlSessionFactory;

    //静态代码块，初始即编译
    static {
            try {
                //获取sqlSessionFactory,第一步：获取sqlSessionFactory对象
                String resource = "mybatis-config.xml";
                InputStream inputStream = Resources.getResourceAsStream(resource);
                sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
            } catch (IOException e) {
                e.printStackTrace();
            }
    }

    //既然有了SqlSessionFactory，顾名思义，我们就可以从中获取SqlSession的实例了
    //SqlSession 完全包含了面向数据库执行的sql命令所需要的所有方法
    public static SqlSession getSqlSession(){
        return sqlSessionFactory.openSession();
    }


}
